The Specialized Animal Resource (SAR) Module has been heavily used since the first funding cycle in 1997. Due to increased demand from current investigators and new investigators, we recently added a second full-time technician, Kathryn Zongolowicz, supported by Case Medical Center (CMC), to assist Heather Butler in breeding the large number of mouse strains utilized by VSRC investigators. We also added a part time (20%) veterinary surgeon, Eugenia Diaconu, also supported by CMC, to teach and assist investigators with difficult ocular injection procedures (e.g., corneal, intravitreal and subretinal). Mutant strains of mice and rats are of considerable value in modern research on the eye. Yet, within the current limitations on budgets, the costs of managing mutant strains is often too high to be added to individual investigator grants, especially for pilot projects. Proper handling of mutant strains represents a major problem in that special expertise is needed to establish the strain from valuable founders, overcome possible breeding problems caused by the mutant phenotype, manage the colonies efficiently in order to produce enough but not too many progeny of the right ages at the right time, and to obtain tissue samples (usually toe or tail snips under anesthesia) for determination of genotypes. With valuable strains, it is also necessary to use isolation cages to avoid infections that reduce the number of surviving progeny and can endanger the entire colony. In collaboration with the genotyping arm of the MB Module, the SAR Module provides a service of breeding, management, characterization and weaning of transgenic animals. In addition to animal management, Eugenia Diaconu, D.V.M. assists in the Module on a part-time basis. The SAR Module provides the critical support that allows our group of vision researchers to take greater advantage of genetically engineered mice and mutant rat lines. The Module was established, in a dedicated space in the Animal Resource Center (ARC) in the basement of the School of Medicine. However, due to the current extensive renovation of the animal care facility at the Case School of Medicine that should be completed by late 2007, the SAR Module breeding room is in the nearby Wolstein Research Building. This facility is a new state-of-the-art barrier animal facility dedicated only to virus-free mice. The facility is controlled for air flow, temperature and humidity, and these parameters are monitored continuously by remote sensors. The breeding facility is located within 200 yards of all investigators in the VSRC, and animals are transferred by the Animal Care Unit staff from the VSRC breeding center (and other breeding centers now located at Wolstein) to each investigator's colony daily or as needed. If more than a cage or two need to be transferred, animal transfer is accomplished in heated/air-conditioned vehicles specifically for this purpose. The ARC is fully accredited and employs a highly skilled staff, including three full-time veterinarians. Space within the facility is assigned on a need basis, and only our full-time veterinary technicians, participating investigators, and ARC staff have access to this room (Appendix A). The investigators of the VSRC have made a dramatic transition over the past five years to studying a large variety of mouse transgenic, knockout and knock-in lines. Having a module with extensive expertise in breeding challenging mouse strains and analyzing and documenting ocular defects meets a critical need for our investigators.